Since its inception in the late 1940s, in what
ways has television had an impact on modern society?

Background

Television is the most widespread form of
communication in the world today. The most common use of tv is as a source
of information and as entertainment for viewers in their
homes.

Although the first practical televisions began
operating in the late 1940s, some of the earliest work took place in 1884
when Paul Nipkow, a German engineer, designed a scanning disk in which light
passing through the disk created crude television images. An electronic
method of scanning was developed by the Russian-born American physicist Vladimir
Zworykin in his iconoscope camera tube of the 1920s. By the 1930s,
cathode rays, or beams of electrons in evacuated glass tubes, were developed
for use in television by Allen DuMont, an American electrical engineer.
His method of picture reproduction is essentially the same as that still
used today. The first home television was demonstrated in Schenectady,
New York in 1928, by Ernst F. W. Alexanderson. The images were small, poor
and unsteady, but the set could be used in the
home.

A television broadcasting boom began after World
War II, and the industry grew rapidly. At first the development of color
television lagged behind because it was technically more complex. Later it
was delayed because color television signals had to use the same channels
as monochrome television, which also had to be receivable in black and white
on monochrome sets. Compatible color television was perfected in
1953.

Television is a system of sending and receiving
pictures and sound by means of electronic signals transmitted through wires
and optical fibers or by electromagnetic radiation. These signals are usually
broadcast from a central television station to reception devices in television
sets in homes or to relay stations used by cable television
providers.

A television camera changes the light from a
scene into an electric video signal. These signals are processed and combined
with other video and audio signals to provide a television program. The program's
electronic signals are then sent to a transmitter, which amplifies them and
combines them with carrier waves (oscillating electric currents that carry
information). The carrier waves are sent through the air via a transmitting
antenna. The waves cause electric currents to form in television-receiving
antennas within their range. A receiver in the television translates the
signal back into pictures and
sounds.

The high-frequency waves radiated by transmitting
antennas can travel only in a straight line. For this reason, transmitting
antennas must be placed on tall buildings or towers. Cable television was
first developed in the late 1940s to serve areas that are blocked from receiving
signals. The signal is picked up on a receiver and redistributed by
cable.

The television receiver translates the pulses
of electric current from the antenna or cable into images and sounds. Once
the viewer selects a channel, the incoming signal is amplified, and the video,
audio and scanning signals are separated from the carrier waves. The audio
system translates the audio portion of the carrier wave back into sound by
running it through an amplifier and a speaker system. The television
picture tube re-creates the original picture by using an electron gun, which
shoots a scanning beam of electrons toward the back of the television screen.
The screen is coated with phosphor, a substance that glows when it is struck
by electrons.

In color television a portion of the video signal
is used to separate out the three color signals. The screen is coated by
tiny dots arranged in groups of three (blue, green and red). Before light
from each beam hits the screen, it passes through a layer of opaque material
that partially blocks the beam corresponding to one color and prevents it
from hitting dots of another color. The viewer sees an image having the entire
spectrum of colors.

Timeline

1907, Boris Rosing transmitted
black-and-white silhouettes of simple shapes using a mechanical mirror-drum
apparatus as a camera and a cathode-ray tube as a receiver.

1919, the Radio Corporation of
America (RCA) is formed.

1923, Vladimir Zworykin patented
the "Iconoscope," an electronic camera tube. By the end of 1923, he had also
produced a picture display tube, the "Kinescope."

1924, John Baird was the first
to transmit a moving silhouette image, using a mechanical system based on
Paul Nipkow's model. The following year he obtained the first actual
television picture, while Zworykin took out the first patent for colour
television.

1926, the National Broadcasting
Company (NBC) is formed by Westinghouse, General Electric and
RCA.

1927, pictures of Herbert Hoover,
U.S. Secretary of Commerce, were transmitted 200 miles from Washington, D.C.
to New York, in the world's first televised speech and first long-distance
television transmission.

1929, John Baird opened the world's
first television studio in London.

1936, there were about 2,000
television sets in use around the world.

1938, Allen DuMont manufactured
the first all-electronic television set for sale to the North American
public.

1941, North America's current
525-line/30-pictures-a-second standard, known as the NTSC (National Television
Standards Committee) standard, was adopted.

1945, baseball was televised for
the first time.

1946, the world's first television
broadcast via coaxial cable was transmitted from New York to Washington
D.C.

1947, a permanent network linking
four eastern U.S. stations was established by NBC.

1950, cable TV began in the U.S.,
while European broadcasters fixed a common picture standard of 625 lines.
Over 100 television stations are in operation in the U.S.

1951 color TV introduced in the
U.S. Unfortunately, for technical reasons, the several million existing
black-and-white receivers in America could not pick up the colour
programs.

1952, the first political ads
appeared on U.S. television networks, when the Democrats bought a half-hour
slot for Adlai Stevenson, who was bombarded with hate mail for interfering
with a broadcast of I Love Lucy. Eisenhower, Stevenson's political opponent,
bought only 20-second commercial spots, and won the election.

1953, TV Guide began publication
this year, and the U.S. began color transmission again; this time
successfully.

1960, the Nixon-Kennedy debates
were televised, marking the first network used a split screen. It wa believed
that television helped Kennedy win the election. Sony developed the first
all-transistor television receiver, making televisions lighter and more portable.
Ninety percent of American homes now owned a television set.

A series of authors have examined the effects
of television on modern politics and public opinion: Matthew Kerbel,
Edited for Television: CNN, ABC and American Presidential
Elections (1998); Karen Johnson-Cartee and Gary Copeland, Manipulation
of the American Voter: Political Campaign Commercials (1997); Warren
Strobel, Late-Breaking Foreign Policy: The News Media's Influence
on Peace Operations (1997); Anthony Corrado and Charles Firestone, eds.,
Elections in Cyberspace: Toward a New Era in American Politics
(1996); Tom Rosenstiel, Strange Bedfellows: How Television and the
Presidential Candidates Changed American Politics, 1992 (1994); E. Dover,
Presidential Elections in the Television Age: 1960-1992 (1994);
Roderick Hart, Seducing America: How Television Charms the Modern
Voter (1994); R. J. Donovan and R. Scherer, Unsilent Revolution:
Television News and American Public Life, 1948-l991 (1992); Austin Ranney,
Channels of Power: The Impact of Television on American Politics
(1983).

For an introduction to the impact of television
on modern society, see: Jay Newman, Religion vs. Television:
Competitors in Cultural Context (1996); Nicholas Abercrombie, Television
and Society (1996); Peter Dahlgren, Television and the Public
Sphere: Citizenship, Democracy and the Media (1995); Aletha
Huston, et al., Big World, Small Screen: The Role of Television
in American Society (1992); Conrad Kottak, Prime-Time Society:
An Anthropological Analysis of Television and Culture
(1990)

For the history of television, see: R.
Burns, Television: An International History of the Formative Years
(1998); Anthony Smith, ed., Television: An International History
(1995); Michael Ritchie, Please Stand By: A Prehistory of
Television (1994); Michael Winship, Television (1988); Albert
Abramson, The History of Television, 1880 to 1941 (1987).